Knock on wood

Michael Williams

Created date

January 18th, 2010

While no one knows exactly where this phrase comes from, most people seem to think that its origin goes back to ancient times when people associated mythological spirits with trees. To tap the tree was to alert tree spirits to your presence, for example. More specifically, Irish tradition has it that you knock on the tree as way of expressing thanks to mythical creatures like leprechauns. Today, the tradition persists, at least as a phrase, in friendly or inane conversation as a way of ensuring good luck. "It won't rain today, knock on wood."